commit b76b163f46b661499921a0049982764a6659bfe7 upstream
With commit 2aa39889c463 ("can: isotp: isotp_bind(): return -EINVAL on incorrect CAN ID formatting") the bind() syscall returns -EINVAL when the given CAN ID needed to be sanitized. But in the case of an unconfirmed broadcast mode the rx CAN ID is not needed and may be uninitialized from the caller - which is ok.
This patch makes sure the result of an inproper CAN ID format is only provided when the address information is needed.
Link: https://lore.kernel.org/all/20220517145653.2556-1-socketcan@hartkopp.net Signed-off-by: Oliver Hartkopp socketcan@hartkopp.net Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de --- net/can/isotp.c | 29 +++++++++++++++++------------ 1 file changed, 17 insertions(+), 12 deletions(-)
diff --git a/net/can/isotp.c b/net/can/isotp.c index 19fffa8676f9..00cb38b4a6f4 100644 --- a/net/can/isotp.c +++ b/net/can/isotp.c @@ -1214,38 +1214,43 @@ static int isotp_bind(struct socket *sock, struct sockaddr *uaddr, int len) struct sock *sk = sock->sk; struct isotp_sock *so = isotp_sk(sk); struct net *net = sock_net(sk); int ifindex; struct net_device *dev; - canid_t tx_id, rx_id; + canid_t tx_id = addr->can_addr.tp.tx_id; + canid_t rx_id = addr->can_addr.tp.rx_id; int err = 0; int notify_enetdown = 0;
if (len < ISOTP_MIN_NAMELEN) return -EINVAL;
if (addr->can_family != AF_CAN) return -EINVAL;
- /* sanitize tx/rx CAN identifiers */ - tx_id = addr->can_addr.tp.tx_id; + /* sanitize tx CAN identifier */ if (tx_id & CAN_EFF_FLAG) tx_id &= (CAN_EFF_FLAG | CAN_EFF_MASK); else tx_id &= CAN_SFF_MASK;
- rx_id = addr->can_addr.tp.rx_id; - if (rx_id & CAN_EFF_FLAG) - rx_id &= (CAN_EFF_FLAG | CAN_EFF_MASK); - else - rx_id &= CAN_SFF_MASK; - - /* give feedback on wrong CAN-ID values */ - if (tx_id != addr->can_addr.tp.tx_id || - rx_id != addr->can_addr.tp.rx_id) + /* give feedback on wrong CAN-ID value */ + if (tx_id != addr->can_addr.tp.tx_id) return -EINVAL;
+ /* sanitize rx CAN identifier (if needed) */ + if (isotp_register_rxid(so)) { + if (rx_id & CAN_EFF_FLAG) + rx_id &= (CAN_EFF_FLAG | CAN_EFF_MASK); + else + rx_id &= CAN_SFF_MASK; + + /* give feedback on wrong CAN-ID value */ + if (rx_id != addr->can_addr.tp.rx_id) + return -EINVAL; + } + if (!addr->can_ifindex) return -ENODEV;
lock_sock(sk);